
* {
  -webkit-box-sizing: border-box;
          box-sizing: border-box;
}



ul {
  font-size: 0;
  position: relative;
  padding: 0;
  width: 480px;
  margin: 40px auto;
  -webkit-user-select: none;
     -moz-user-select: none;
      -ms-user-select: none;
          user-select: none;
}

li {
  display: inline-block;
  width: 160px;
  height: 60px;
  background: #39CCCC;
  font-size: 16px;
  text-align: center;
  line-height: 60px;
  color: #fff;
  text-transform: uppercase;
  position: relative;
  overflow: hidden;
  cursor: pointer;
}

.slider {
  display: block;
  position: absolute;
  bottom: 0;
  left: 0;
  height: 4px;
  background: yellow;
  -webkit-transition: all 0.5s;
  transition: all 0.5s;
}
/*  Ripple */

.ripple {
  width: 0;
  height: 0;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.4);
  -webkit-transform: scale(0);
          transform: scale(0);
  position: absolute;
  opacity: 1;
}

.rippleEffect {
  -webkit-animation: rippleDrop .6s linear;
          animation: rippleDrop .6s linear;
}

@-webkit-keyframes rippleDrop {
  100% {
    -webkit-transform: scale(2);
            transform: scale(2);
    opacity: 0;
  }
}

@keyframes rippleDrop {
  100% {
    -webkit-transform: scale(2);
            transform: scale(2);
    opacity: 0;
  }
}